Gantry scraper

ABSTRACT

This gantry scraper adapted to transfer or pick up material from a heap or hook in a silo or like enclosure is mounted above a pit of said silo or the like and adapted to travel therealong; it comprises a pair of scraper arms, namely a primary arm and a secondary arm, mounted to the gantry structure and each provided with an endless conveyor chain, the upper ends of said arms being hingedly interconnected; pendular-motion means are provided for connecting the lower end of the secondary arm to the gantry structure and enable said secondary arm to move to a position in which it is substantially co-extensive with said primary arm.

Bluntzer GANTRY SCRAPER Rene Bluntzer, Thann, France Aug. 28, 1973 633,005 5/1963 Belgium 2l4/l0 [75] Inventor:

Primary ExaminerGerald M. Forlenza [73] Assignee. Ameco S.A., Klngersheun, France Assistant ExamiMr Frank E. Werner Filed: M r- 1, 1971 Attorney-Robert E. Burns et al. [21] Appl. No.: 129,770

57 ABSTRACT [30] Foreign Application Priority Data 1 Mar. 31, 1970 France 7011804 This gantry scraper adapted to transfer or pick up material from a heap or hook in a silo or like enclosure is [52] U.S. CI. 198/36, 214/10 moun ed above a pit of sai silo or the like and adapted [51] int. Cl. 865 59/00 to a e he g; it c mprises a pair of scraper [58] Field of Search 214/10; 198/9, 36; a s. ame y a p y arm and a seconda y m, 37/192 R, 192 A mounted to the gantry structure and each provided with an endless conveyor chain, the upper ends of said [56] R ferences Cited arms being hingediy interconnected; pendular-motion UNITED STATES PATENTS means are provided for connecting the lower end of the secondary arm to the gantry structure and enable said 2:22: secondary arm to move to a position in which it is substantially co-extensive with said primary arm.

FOREIGN PATENTS 0R APPLICATIONS 1,148,425 4/1969 Great Britain 198/36 2 Claims, 2 Drawing Figures 1 1O 11 l 12 e 3 80 8b 9 =2913141 EU A z r 1/ Z =z\ f a 1 1 1, Q e "35in;

Patented Aug. 28, 1973 3,754,633

2 Sheets-Sheet 1 Pa tented Aug. 28, 1973 3,754,633

2 Sheets-Sheet 2 GANTRY SCRAPER BACKGROUND OF THE INVENTION The present invention relates to gantry scrapers.

As a rule, gantry scrapers comprise two scraping arms, namely a primary arm and a secondary arm. The primary arm carries along the stored products or materials towards transfer means such as endless belt conveyors or the like. The secondary arm is adapted to drive the products or materials towards the primary arm. As the heap, pile or hook decreases, the two arms supported by the gantry are lowered and move towards the bottom of the silo or like storage means. The primary arm rotates about a pivot consisting of the lower driving shaft. The secondary arm, of which the upper head or end is connected through any suitable means to the upper head or end of the primary arm, is adapted to slide downwards along a rectilinear path. To this end, the gantry comprises an inclined guideway in which a roller connected through a rod to the lower end of the secondary arm is adapted to travel. However, the space left between heap and gantry is very small, thus limiting the guideway inclination as well as the rod length. Therefore, the distance from the lowermost point of the secondary am in the end position and the gantry is relatively short and limits the height available for storing the products or materials.

SUMMARY OF THE INVENTION It is the essential object of the present invention to avoid the inconvenience set forth in the above preamble by providing a device permitting of increasing the distance between the bottom of the gantry and the bottom of the storage silo or like enclosure while affording a relatively long stroke of said secondary arm. Thus, the storage heap or hook is increased by either providing a pit into which said secondary arm can be lowered, or raising the gantry on the side of the secondary arm, thus increasing the volume available for the storage of the loose products or materials.

To this end, the present invention is concerned chiefly with a device adapted to impart a relative mobility to the secondary arm of a gantry scraper, characterized in that it comprises penduIar-motion means for placing said secondary arm in co-extensive relationship to said primary arm, said means being combined with vertical-motion means for lowering said secondary arm into the pit of the silo or like storage means during a second step.

BRIEF DESCRIPTION OF THE DRAWINGS In order to afford a clearer understanding of this invention a typical form of embodiment thereof will now be described by way of illustration with reference to the attached drawing, in which:

FIG. 1 is a diagrammatic elevational view showing a gantry scraper comprising the arrangement of this invention, and,

FIG. 2 is a view similar to FIG. 1 showing a modified form of embodiment of the device of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIG. 1, the gantry scraper 1 adapted to travel in a silo 2 in a direction perpendicular to the plane of the Figure comprises a gantry structure 3 having the shape of an inverted V and bearing with its lower ends 4 and 5 on rails 6 and 7, respectively. This gantry structure 3 constitutes the support of a pair of scraper arms 8, 9, with arm 8 constituting the primary arm and arm 9 the secondary arm. Each arm 8, 9 comprises in a manner known per so an endless scraping chain 8a, 9a carrying the scraping tools; these chains being driven from suitable and known power means (not shown).

The head 10 at the upper end of primary arm 8 is connected through a pivoted rod 11 to the head 12 of the secondary arm 9, which is also located at the upper end of this arm.

The lower shaft 13 of secondary arm 9 is connected via hinge means to a first link 14 connected in turn to a second link 15. A hinge pin 16 permits the mutual pivotal connection of links 14 and 15. The lower end of second link is connected through a fixed pivot pin 18 to the gantry structure 3.

With this assembly the storage silo or like enclosure may comprise a pit-forming bottom 19 or alternatively the rail 7 may be disposed at a higher level, for instance on a wall 20, a shown in FIG. I. This wall 20 permits to raise the level of the lower limit 21 of the heap or pile of product 22 to a higher level 23. Thus, the storage volume is increased by the quantity illustrated by the hatched portion 24 of FIG. I.

When the height of the heap of material or product to be transferred decreases, the primary and secondary arms 8, 9 are lowered down to a substantially horizontal position in which they are substantially aligned on the bottom 19 of silo 2, as shown in dotted lines in FIG. 1. Hoisting means, such as babies 8b and 9b are provided for lifting the two arms, respectively.

Referring now to FIG. 2, it may be reminded that siloed or like stored products or materials tend to agglomerate and form lumps. By utilizing the abovedescribed device it may happen that a certain volume of product remains in the form of a relatively thick compact layer against the wall 20 so that it is not transferred by the secondary arm 9. According to a modified form of embodiment of the present invention, a pendular motion is imparted to the secondary arm 9 and then the assembly comprising this secondary arm 9 and the primary arm 8 is lowered in a substantially vertical direction. The device comprises a winch 25 mounted to the gantry structure3 and a. cable 26 interconnecting said winch and said secondary arm 9. The cable 26 is wound on a return pulley 27 carried by the gantry structure at a lower level than said winch 25. During a first phase, the cable 26 supporting the end of the secondary arm describes a circular arc centered to the axis of said return pulley 27. When the secondary arm 9 is co-extensive with the primary arm 8 as shown by the reference numeral 28, and the length of the assembly comprising said arms 8 and 9 attains its maximum permissible value, the winch 25 is operated to unwind the cable 26 and thus this assembly is lowered to the bottom 19 of the storage silo or like enclosure, by describing a circular arc centered to the axis of power shaft 29 of primary arm 8, so as to eventually assume the position designated by the reference numeral 30.

According to a modified form of embodiment, the winch and cable system is replaced either by a telescopic tube or by a cylinder-and-piston actuator; in this case, the telescopic tube or actuator pivots about the hinge pin 27 and becomes operative only when the arms 8 and 9 are in position 28.

Although a specific form of embodiment of this invention has been illustrated and described herein, it will readily occur to those conversant with the art that various modifications and variations may be brought thereto without departing from the spirit and scope of the invention as set forth in the appended claims.

What I claim is:

1. In a gantry scraper for loading bulk material from a storage heap; a gantry; a scraper loader for loading bulk material from a storage heap of said material comprising a first scraper jib having first scraper means thereon for scraping said material from said storage heap to a loading position, and a second scraper jib having second scraper means thereon for scraping said material on said storage heap and feeding said first scraper means with said material, said first scraper jib and said second scraper jib each having a longitudinal axis and said second scraper jib having a longitudinal length less than said first scraper jib; means pivotally connecting a lower end of said first scraper jib to said gantry at an elevation above the elevation of the bottom of said storage heap; means pivotally connecting said second scraper jib to said first scraper jib; and a link mechanism having means means for effecting pivotal movement of said second scraper jib and said first scraper jib to a position wherein the longitudinal axis of both said first scraper jib and said second scraper jib are horizontal and said second scraper jib is disposed substantially as an extension of said first scraper jib and including means to position the longitudinal axis of said second scraper jib substantially horizontal and at an elevation lower than the elevation of said means pivotally connecting said first scraper arm to said gantry, said link mechanism for effecting pivotal movement comprising a first link, means pivotally connecting said first link at one point to said second scraper jib, a second link, means pivotally connecting said second link at a first point to said first link at a point spaced from said one point, and means pivotally connecting said second link at a second point to said gantry.

2. A gantry scraper according to claim 1: wherein said means pivotally connecting said second link at said second point to said gantry comprises means defining said second point at an elevation higher than the elevation of said means pivotally connecting said first scraper jib to said gantry. 

1. In a gantry scraper for loading bulk material from a storage heap; a gantry; a scraper loader for loading bulk material from a storage heap of said material comprising a first scraper jib having first scraper means thereon for scraping said material from said storage heap to a loading position, and a second scraper jib having second scraper means thereon for scraping said material on said storage heap and feeding said first scraper means with said material, said first scraper jib and said second scraper jib each having a longitudinal axis and said second scraper jib having a longitudinal length less than said first scraper jib; means pivotally connecting a lower end of said first scraper jib to said gantry at an elevation above the elevation of the bottom of said storage heap; means pivotally connecting said second scraper jib to said first scraper jib; and a link mechanism having means means for effecting pivotal movement of said second scraper jib and said first scraper jib to a position wherein the longitudinal axis of both said first scraper jib and said second scraper jib are horizontal and said second scraper jib is disposed substantially as an extension of said first scraper jib and including means to position the longitudinal axis of said second scraper jib substantially horizontal and at an elevation lower than the elevation of said means pivotally connecting said first scraper arm to said gantry, said link mechanism for effecting pivotal movement comprising a first link, means pivotally connecting said first link at one point to said second scraper jib, a second link, means pivotally connecting said second link at a first point to said first link at a point spaced from said one point, and means pivotally connecting said second link at a second point to said gantry.
 2. A gantry scraper according to claim 1: wherein said means pivotally connecting said second link at said second point to said gantry comprises means defining said second point at an elevation higher than the elevation of said means pivotally connecting said first scraper jib to said gantry. 